A passive wireless sensor platform for chemical and biological agents

Passive wireless sensors can be used to detect chemical or biological agents without the use of probes or wires and without the use of a battery. This paper presents a platform used as a passive wireless sensor to detect certain chemicals of interest. The wireless sensor is powered through an interrogator which sends magnetic/inductive waves to the remote sensor. The sensor converts the power to direct current and then sends back a portion of the power through radio frequency waves with altered frequency, amplitude, and phase. The characteristics of the received signal contain the information about the agent of interest.